Communication systems typically include a plurality of communication units, such as mobile or portable radio units, that are geographically distributed among various base sites. The communication units wirelessly communicate with the base sites and each other, and are often logically divided into various talkgroups. Communication systems may be organized as trunked systems, where a plurality of radio frequency (RF) communication resources are allocated amongst multiple users or groups by assigning the base sites and RF channels within a coverage area on a call-by-call basis, or as conventional (non-trunked) systems where RF communication resources are dedicated to one or more users or groups. In trunked systems, or in mixed trunked and conventional systems, there is usually provided a central controller/server (sometimes called a “zone controller”) for allocating RF communication resources among a group of sites. The zone controller may reside within a single device or multiple devices and may be located at a fixed equipment site or may be distributed among the base sites.
Communication systems typically utilize one or more methods for detecting and compensating for network congestion. In current systems, congestion detection and control is generally performed by one or more components of the fixed network equipment, such as the base site or zone controller. This results in several drawbacks. First, it requires the fixed network equipment to devote significant processing time to monitoring the congestion on each communication channel, thus utilizing valuable resources. Additionally, the fixed network equipment, while capable of detecting the presence of congestion, typically has no knowledge of the specific amount of resources required by each particular communication unit at any given time. As a result, the fixed network equipment is not capable of adequately reconfiguring channel assignments to best utilize available channel resources when congestion is present.
Skilled artisans will appreciate that elements in the figures are illustrated for simplicity and clarity and have not necessarily been drawn to scale. For example, the dimensions and/or relative positioning of some of the elements in the figures may be exaggerated relative to other elements to help improve the understanding of various embodiments of the present disclosure. Also, common but well-understood elements that are useful or necessary in a commercially feasible embodiment are not often depicted in order to facilitate a less obstructed view of these various embodiments of the present disclosure. It will be further appreciated that certain actions and/or steps may be described or depicted in a particular order of occurrence while those skilled in the art will understand that such specificity with respect to sequence is not actually required. It will also be understood that the terms and expressions used herein are to be defined with respect to their corresponding respective areas of inquiry and study except where specific meaning have otherwise been set forth herein.